I work on a project "SignInLogeIn" using Visual Basic.NET.
I save the user informations in text file.
the name of the file is "data.txt".
to create a new account in my program. you must enter the name,email,password and the program write the informations in textfile.
i use "Streamwritter" to write the informations.
when user create a new account The program checks if the email entered by the user is already in the text file that contains the users' information.
and the program checks from informations by "StreamReader". it reads the information in text file and checks.
I have the problem.
when I CREATE A new account. problem appears.
and the problem is
"
An unhandled exception of type 'System.IO.IOException' occurred in mscorlib.dll
Additional information: The process cannot access the file 'D:\1- Anas Files\Projects\VisualBasic.NET\SignInLogIn\SignInLogIn\SignInLogIn\bin\Debug\Data.txt' because it is being used by another process.
"
I think the problem is that I used the file twice
Once to write and once to read.
The error occurs in this line "Dim sw As New StreamWriter("Data.txt")".
how can i solve this problem ?
this is the code of "SignIn" button
Private Sub btnSignIn_Click(sender As Object, e As EventArgs) Handles btnSignIn.Click
Dim strEmail As String = txtEmail.Text
Dim Reg As New Regex("^\w+([-_.]\w+)*#\w+([-.]\w+)*\.\w+([-.]\w+)*$")
If txtUserName.Text.Trim() = "" Or txtEmail.Text.Trim() = "" Or txtPassword.Text.Trim() = "" Then
MsgBox("Please Enter All Input")
If Not Reg.IsMatch(strEmail) Then
MsgBox("Please Enter Email")
End If
Else
Dim sr As New StreamReader("Data.txt")
Dim sw As New StreamWriter("Data.txt")
Dim strPerson As String = txtUserName.Text & ";" & txtEmail.Text & ";" & txtPassword.Text
Dim line As String = ""
Do
line = sr.ReadLine()
Dim arrData As String() = line.Split(";")
If arrData(1) = strEmail Then
MsgBox("Please Change Email")
Else
sw.WriteLine(strPerson)
sw.Close()
End If
Loop While line <> Nothing
sr.Close()
End If
End Sub
You open twice the same file. First, to read and second to write, this is why you cannot write.
Dim sr As New StreamReader("Data.txt")
Dim lines As String = sr.ReadToEnd().Split(Environment.NewLine)
sr.Close()
Dim strPerson As String = txtUserName.Text & ";" & txtEmail.Text & ";" & txtPassword.Text
Dim sw As New StreamWriter("Data.txt")
For Each line As String In lines
Dim arrData As String() = line.Split(";")
If arrData(1) = strEmail Then
MsgBox("Please Change Email")
Exit For
Else
sw.WriteLine(strPerson)
Exit For
End If
Next
sw.Close()
Streams need to be closed and disposed. They are usually put in Using blocks.
I wasn't quite sure of the program flow you wanted. It seemed, since you created a writer and a reader you intended to add to user to the file if they were not listed.
I broke out some of the code into separate methods. I used System.IO since we have a simple text file.
Private Sub btnSignIn_Click(sender As Object, e As EventArgs) Handles btnSignIn.Click
If ValidInput() Then
Dim strPerson As String = $"{txtUserName.Text};{txtEmail.Text};{txtPassword.Text}"
If Not IsUserInFile(strPerson) Then
File.AppendAllText("Data.txt", strPerson & Environment.NewLine)
End If
End If
End Sub
Private Function ValidInput() As Boolean
Dim strEmail As String = txtEmail.Text
Dim Reg As New Regex("^\w+([-_.]\w+)*#\w+([-.]\w+)*\.\w+([-.]\w+)*$")
If txtUserName.Text.Trim() = "" OrElse txtEmail.Text.Trim() = "" OrElse txtPassword.Text.Trim() = "" Then
MsgBox("Please Enter All Input")
Return False
If Not Reg.IsMatch(strEmail) Then
MsgBox("Please Enter Email")
Return False
End If
End If
Return True
End Function
Private Function IsUserInFile(Person As String) As Boolean
Dim p = Person.Split(";"c)
Dim lines = File.ReadAllLines("Data.txt")
For Each line In lines
If Person = line Then
Return True
End If
Dim fields = line.Split(";"c)
If fields(0) = p(0) AndAlso fields(2) = p(2) AndAlso fields(1) <> p(1) Then
MessageBox.Show("Please Change Email")
Return False
End If
Next
Return False
End Function
This is going to get messy and slow if there are too many users. This info should really be in a database. The worst thing is the passwords should always be salted and hashed; never stored as plain text even is a database.
I am making an installer for a flight sim thing but when I use them following code I get this message: Conversion from string "F:\Steam\steamapps\common\FSX" to type 'Double' is not valid
Here is the code:
Private Sub FsX1Button2_Click(sender As Object, e As EventArgs) Handles FsX1Button2.Click
Try
If TextBox1.Text = Not "" Then
My.Computer.FileSystem.DeleteFile(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Instruments_lm.dds")
My.Computer.FileSystem.DeleteFile(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Instruments.dds")
My.Computer.FileSystem.DeleteFile(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Countertops2_lm.dds")
My.Computer.FileSystem.DeleteFile(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Countertops2.dds")
Dim bravo() As Byte = My.Resources.ControlTower_Countertops2
System.IO.File.WriteAllBytes(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Countertops2.dds", bravo)
Dim charlie() As Byte = My.Resources.ControlTower_Countertops_lm
System.IO.File.WriteAllBytes(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Countertops2_lm.dds", charlie)
Dim delta() As Byte = My.Resources.ControlTower_Instruments
System.IO.File.WriteAllBytes(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Instruments.dds", delta)
Dim foxtrot() As Byte = My.Resources.ControlTower_Instruments_lm
System.IO.File.WriteAllBytes(TextBox1.Text & "\SimObjects\Misc\ControlTower\texture\ControlTower_Instruments_lm.dds", foxtrot)
Me.Hide()
MsgBox("Installed successfully", MsgBoxStyle.Information, "")
End
Else
MsgBox("Select path", MsgBoxStyle.Exclamation, "")
End If
Catch ex As Exception
MsgBox("Error exporting the files (" + ex.Message + ")", MsgBoxStyle.Critical, "Error")
End Try
End Sub
Private Sub FsX1Button1_Click(sender As Object, e As EventArgs) Handles FsX1Button1.Click
FolderSelect.ShowDialog()
TextBox1.Text = FolderSelect.SelectedPath
End Sub
So you press the button and select the folder and it sets TextBox1 to the file path. Then it adds the files.
However, When i use the following code:
Try
My.Computer.FileSystem.CreateDirectory("C:\ProjectRazerFiles")
Dim b() As Byte = My.Resources.ControlTower_Countertops2
System.IO.File.WriteAllBytes("C:\ProjectRazerFiles\ControlTower_Countertops2.dds", b)
Dim c() As Byte = My.Resources.ControlTower_Countertops_lm
System.IO.File.WriteAllBytes("C:\ProjectRazerFiles\ControlTower_Countertops2_lm.dds", c)
Dim d() As Byte = My.Resources.ControlTower_Instruments
System.IO.File.WriteAllBytes("C:\ProjectRazerFiles\ControlTower_Instruments.dds", d)
Dim f() As Byte = My.Resources.ControlTower_Instruments_lm
System.IO.File.WriteAllBytes("C:\ProjectRazerFiles\ControlTower_Instruments_lm.dds", f)
MsgBox("Exported successfully", MsgBoxStyle.Information, "")
Catch ex As Exception
MsgBox("Error exporting the files (" + ex.Message + ")", MsgBoxStyle.Critical, "Error")
End Try
It works?
Can you help me with the top one please?
Any help would be gratefully appreciated
The issue is presumably here:
If TextBox1.Text = Not "" Then
That code doesn't make sense. It's trying to negate an empty String and compare the result to another String. If you're trying to test that the TextBox is not empty then that would be like this:
If TextBox1.Text <> "" Then
First, you obviously have option strict set to off, turn it on and fix all of the errors you get (including this one). If you have more than a few hundred, you should turn it on at the project level and off at the file level.
The Not "" is obviously turning the empty string into a double (using the equivalent of Val("")) and then performing a bitwise Not on it and then trying to compare the result to TextBox1.Text by converting it's value to a double, which it fails to do and thus your exception.
Option Strict Off allows these types of comparisions, and in some cases it even works out to roughly what you meant to happen. In other cases, as this example shows, it just causes a compile time error to become a runtime error. That is seldom an improvement.
I have such kind of data in a text file:
12343,M,Helen Beyer,92149999,21,F,10,F,F,T,T,T,F,F
54326,F,Donna Noble,92148888,19,M,99,T,F,T,F,T,F,T
99999,M,Ed Harrison,92147777,28,F,5,F,F,F,F,F,F,T
88886,F,Amy Pond,92146666,31,M,2,T,F,T,T,T,T,T
37378,F,Martha Jones,92144444,30,M,5,T,F,F,F,T,T,T
22444,M,Tom Scully,92145555,42,F,6,T,T,T,T,T,T,T
81184,F,Sarah Jane Smith,92143333,22,F,5,F,F,F,T,T,T,F
97539,M,Angus Harley,92142222,22,M,9,F,T,F,T,T,T,T
24686,F,Rose Tyler,92142222,22,M,5,F,F,F,T,T,T,F
11113,F,Jo Grant,92142222,22,M,5,F,F,F,T,T,T,F
I want to extract the Initial of the first name and complete surname. So the output should look like:
H. Beyer, M
D. Noble, F
E. Harrison, M
The problem is that I should not use String Split function. Instead I have to do it using any other way of string handling.
This is my code:
Public Sub btn_IniSurGen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_IniSurGen.Click
Dim vFileName As String = "C:\temp\members.txt"
Dim vText As String = String.Empty
If Not File.Exists(vFileName) Then
lbl_Output.Text = "The file " & vFileName & " does not exist"
Else
Dim rvSR As New IO.StreamReader(vFileName)
Do While rvSR.Peek <> -1
vText = rvSR.ReadLine() & vbNewLine
lbl_Output.Text += vText.Substring(8, 1)
Loop
rvSR.Close()
End If
End Sub
You can use the TextFieldParserClass. It will parse the file and return the results directly to you as a string array.
Using MyReader As New Microsoft.VisualBasic.FileIO.
TextFieldParser("c:\logs\bigfile")
MyReader.TextFieldType =
Microsoft.VisualBasic.FileIO.FieldType.Delimited
MyReader.Delimiters = New String() {","}
Dim currentRow As String()
'Loop through all of the fields in the file.
'If any lines are corrupt, report an error and continue parsing.
While Not MyReader.EndOfData
Try
currentRow = MyReader.ReadFields()
' Include code here to handle the row.
Catch ex As Microsoft.VisualBasic.FileIO.MalformedLineException
MsgBox("Line " & ex.Message &
" is invalid. Skipping")
End Try
End While
End Using
For your wanted result, you may changed
lbl_Output.Text += vText.Substring(8, 1)
to
'declare this first
Dim sInit as String
Dim sName as String
sInit = vText.Substring(6, 1)
sName = ""
For x as Integer = 8 to vText.Length - 1
if vText.Substring(x) = "," Then Exit For
sName &= vText.Substring(x)
Next
lbl_Output.Text += sName & ", " & sInit
But better you have more than one lbl_Output ...
Something like this should work:
Dim lines As New List(Of String)
For Each s As String In File.ReadAllLines("textfile3.txt")
Dim temp As String = ""
s = s.Substring(s.IndexOf(","c) + 1)
temp = ", " + s.First
s = s.Substring(s.IndexOf(","c) + 1)
temp = s.First + ". " + s.Substring(s.IndexOf(" "c), s.IndexOf(","c) - s.IndexOf(" "c)) + temp
lines.Add(temp)
Next
The list Lines will contain the strings you need.
Okay so for an internship project i'm making a Journal with streamwriters and streamreaders.
I have to to where you can create an account with a name, Username, and Password. I also have it to where it creates a txt file in that persons name when you create the account. Now, they login and it brings them to the journal page. The Journal Page for the most part has a Date for your journal Entry, the title of the journal and the journal entry text itself.
The problem that I am having is that when you click the button to create/edit a journal entry, it goes through a sub routine that checks if that journal exists (Meaning that there is already one for that date) or not. If it doesn't exist, then it should create a new one at the bottom of the text file. If it does exist then it should edit the lines in which that journal are stationed in the text file.
Code:
Private Sub CreateBtn_Click(sender As System.Object, e As System.EventArgs) Handles CreateBtn.Click
Errors = ""
Dim TempCounter As Integer = 0
If TitleTxt.Text = "" Then
Errors = "You must enter a title." & vbCrLf
End If
If JournalTextRtxt.Text = "" Then
Errors &= "You must enter an entry for the journal."
End If
If Errors <> "" Then
MessageBox.Show("There's an error in creating/editing your journal." & vbCrLf & "Error(s):" & vbCrLf & Errors, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
Else
JournalDate = DateTimePicker1.Value
JournalTitle = TitleTxt.Text
JournalText = JournalTextRtxt.Text
arrJournalEntries(TempCounter).TheDate = JournalDate
arrJournalEntries(TempCounter).Title = JournalTitle
arrJournalEntries(TempCounter).JournalEntry = JournalText
CheckAndWrite()
End If
End Sub
Private Sub CheckAndWrite()
Dim Reader As New StreamReader(MyName & ".txt", False)
Dim Sline As String = Reader.ReadLine
Counter = 0
Do Until (Sline Is Nothing) 'Perform the code until the line in the text file is blank
If Not Sline Is Nothing Then 'If the line in the text file is NOT blank then
For i As Integer = 1 To 3
Select Case i
Case 1
arrJournalEntries(Counter).TheDate = Sline
Sline = Reader.ReadLine
Case 2
arrJournalEntries(Counter).Title = Sline
Sline = Reader.ReadLine
Case 3
arrJournalEntries(Counter).JournalEntry = Sline
Sline = Reader.ReadLine
End Select
Next
End If
JournalDate = arrJournalEntries(Counter).TheDate
Time = DateTimePicker1.Value
MsgBox("Journal Date = " & JournalDate & vbCrLf & "Today's Date = " & Time)
If Time = JournalDate Then
JournalFound = True
Else
Counter += 1
JournalFound = False
End If
Loop
Reader.Close()
Try
If Sline Is Nothing Or JournalFound = False Then
MsgBox("Your journal is now going to be created.")
JournalDate = DateTimePicker1.Value
JournalTitle = TitleTxt.Text
JournalText = JournalTextRtxt.Text
arrJournalEntries(Counter).TheDate = JournalDate
arrJournalEntries(Counter).Title = JournalTitle
arrJournalEntries(Counter).JournalEntry = JournalText
Dim Writer As New StreamWriter(MyName & ".txt", True)
Do Until (arrJournalEntries(Counter).TheDate = Nothing)
Writer.WriteLine(arrJournalEntries(Counter).TheDate)
Writer.WriteLine(arrJournalEntries(Counter).Title)
Writer.WriteLine(arrJournalEntries(Counter).JournalEntry)
Counter += 1
Loop
Writer.Close()
End If
If JournalFound = True Then
MsgBox("Your journal is now going to be edited.")
JournalDate = DateTimePicker1.Value
JournalTitle = TitleTxt.Text
JournalText = JournalTextRtxt.Text
arrJournalEntries(Counter).TheDate = JournalDate
arrJournalEntries(Counter).Title = JournalTitle
arrJournalEntries(Counter).JournalEntry = JournalText
Dim Writer As New StreamWriter(MyName & ".txt", True)
Do Until (arrJournalEntries(Counter).TheDate = Nothing)
Writer.WriteLine(arrJournalEntries(Counter).TheDate)
Writer.WriteLine(arrJournalEntries(Counter).Title)
Writer.WriteLine(arrJournalEntries(Counter).JournalEntry)
Counter += 1
Loop
Writer.Close()
End If
Catch ex As Exception
MessageBox.Show("An error has occured" & vbCrLf & vbCrLf & "Original Error:" & vbCrLf & ex.ToString)
End Try
End Sub`
The problem that's occuring is that it's not only writing in the first time wrong. When it's supposed to say it's going to edit, it doesn't, it just says creating. But it just adds on to the file. After pressing the button 3 times with the current date. and the Title being "Test title", and the journal entry text being "Test text". This is what occured.
It should just be
7/10/2012 3:52:08 PM
Test title
Test text
7/10/2012 3:52:08 PM
Test title
Test text
the whole way through. but of course if it's the same date then it just overwrites it. So can anybody please help me?
You are only filtering your array by the date, so it looks like you have an object with a date but no title or text:
Do Until (arrJournalEntries(Counter).TheDate = Nothing)
The "quick" fix:
Do Until (arrJournalEntries(Counter).TheDate = Nothing)
If arrJournalEntries(Counter).Title <> String.Empty Then
Writer.WriteLine(arrJournalEntries(Counter).TheDate)
Writer.WriteLine(arrJournalEntries(Counter).Title)
Writer.WriteLine(arrJournalEntries(Counter).JournalEntry)
End If
Counter += 1
Loop
Do consider getting rid of the array and using a List(of JournalEntry) instead. Your code looks difficult to maintain in its current state.
I've got 3 or 4 patterns that I'm comparing user input against and I need to figure out if the user input matches one of the patters and to return the match if it does.
Since the input is multiline, I'm passing each individual line like so:
Dim strRawInput() As String = Split(txtInput.Text, vbCrLf)
Dim strInput As String
txtOutput.Text = ""
For Each strInput In strRawInput
strInput.Trim(vbCr, vbLf, Chr(32))
Validation(strInput)
Next
Then I have this to find matches:
Dim m As Match
For i = 0 To strValidator.Length - 1
Dim r As New Regex(strValidator(i))
m = r.Match(strInput)
If m.Success Then
txtOutput.Text = txtOutput.Text & "Success: " & m.ToString & vbCrLf
Exit Sub
Else
End If
Next
txtOutput.Text = txtOutput.Text & "Not this time" & vbCrLf
How can I do this more efficiently? Also, I added the Exit Sub there to avoid showing the "Not this time" message even after a match is found (if the match is with one of the later patterns in the array), but I'd like to find a better way of doing that too.
Thanks in advance.
Rather than generating your Regexs in the loop, generate them one time at the startup of the application. So maybe something like:
Private Shared m_regexes As New List(Of Regex)
Shared Sub New()
For Each v As String In strValidator
m_regexes.Add(New Regex(v))
Next
End Sub
And then you can change your other code to:
For Each r As Regex In m_regexes
Dim m As Match = r.Match(strInput)
If m.Success Then
txtOutput.Text = txtOutput.Text & "Success: " & m.ToString & vbCrLf
Exit Sub
Else
End If
Next
Regarding the Exit Sub, I think it's fine, You've discovered that it matches at least one pattern, so why continue to evaluate the rest. But if you don't like methods that can "return" in multiple places, you could just replace it with a Boolean and a Exit For as:
Dim found as Boolean = false
For Each ...
If IsMatch Then
found = True
Exit For
End If
Next
If Found Then
....
Else
.....
End If
Hmm if that's the case then wouldn't this be even better?
For i = 0 To strValidator.Length - 1
Dim r As New Regex(strValidator(i))
Dim m As Match = r.Match(strInput)
If m.Success Then
txtOutput.Text = txtOutput.Text & "Success: " & m.ToString & vbCrLf
Exit Sub
End If
Next